方式一、Action中定义成员变量,并生成get/set方法,在JSP页面可以取到这个变量值。
例如:action类:
public class BookAction extends ActionSupport {
private Book book;
private List<Book> books;
...
public String findBook(){
books=bookService.findBook(book.getBookName());
return SUCCESS;
}
public Book getBook() {
return book;
}
public void setBook(Book book) {
this.book = book;
}
public List<Book> getBooks() {
return books;
}
public void setBooks(List<Book> books) {
this.books = books;
}
...
}
jsp页面:用OGNL表达式
<s:iterator id="b" value="books">
<tr>
<td><s:property value='#b.getBookId()'/> </td>
<td><s:property value='#b.getBookName()'/> </td>
</tr>
</s:iterator>
或EL表达式
<s:iterator value="books" var="b">
<tr>
<td>${b.bookId}</td>
<td>${b.bookName}</td>
</tr>
</s:iterator>
方式二、但是定义的成员变量多了,感觉整个Action的代码就很长了。这个时候可以使用一些Servlet API进行值的存取操作:HttpServletRequest、HttpSession和ServletContext。Struts2对这个三个对象用Map进行了封装,我们就可以使用Map对象来存取数据了。
ActionContext actionContext = ActionContext.getContext();
//get HttpServletRequest
Map<String,Object> request = (Map) actionContext.get("request");
request.put("a", "a is in request");
//get HttpSession
//Map<String,Object> session = (Map) actionContext.get("session");
Map<String,Object> session = actionContext.getSession();
session.put("b", "b is in session");
//get ServletContext
//Map<String,Object> application = (Map) actionContext.get("application");
Map<String,Object> application = actionContext.getApplication();
application.put("c", "c is in application");
jsp
${a}
${b}
${c}
or
${requestScope.a}
${sessionScope.b}
${applicationScope.c}
或者直接使用ActionContex类的put()方法:
ActionContext.getContext().put("greeting", "你好虫虫");
然后在结果页面中,从请求对象中取出greeting属性,如下:
${requestScope.greeting} 或者 <%=request.getAttribute("greeting")%>
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作者:qq_29606237
来源:CSDN
原文:https://blog.csdn.net/qq_29606237/article/details/79619845
版权声明:本文为博主原创文章,转载请附上博文链接!